So this is a bit smaller of a project and does not involve long term flying, but it really is a tiny version of what I am doing. I found this kids paper and he has a website from a couple years ago. I think this was an engineering project for school. I will review his findings to see if there is anything out there useful.

https://garethnunns.com/wp-content/uploads/Flying,-Autonomous-WiFi-Gareth-Nunns.pdf

Web page and you tube video

https://garethnunns.com/blog/flying-autonomous-wifi/